As a system according to a prior art for transmitting video and audio data among a plurality of node devices, there has been known a system which uses an HDMI specified in Non-Patent Document 1. In the HDMI system, a node device (for example, an audio and visual reproducing device such as a DVD (Digital Versatile Disk) player) at a transmitter side for transmitting the video and audio data reads EDID (Extended Display Identification Data) of a node device (for example, a TV) at a receiver side via a DDC (Display Data Channel) so as to acquire required format information. This format information includes video output formats (video output specifications) and audio output formats (audio output specifications) that the node device at the receiver side supports. The node device at the transmitter side determines output formats of data to be transmitted based on the acquired format information. Information on a decided video output format is multiplexed with the video data, and transmitted to the node device at the receiver side.
When a user presses a Play button of the node device at the transmitter side, the node device at the transmitter side transmits an Active Source message to the node device at the receiver side. In response to this, input-switching is done at the node device at the receiver side, and the node device at the receiver side can display pictures reproduced by the node device at the transmitter side instantly.
In addition, Patent Document 1 discloses an AV system configured to include a display device, a plurality of video devices connected to the display device, and remote controllers for controlling the video devices, respectively. In the AV system, it is possible to operate the respective video devices with the remote controls to the display. Each of the remote controllers transmits a remote control code including at least one of a manufacturer code corresponding to the remote controller and a device code, to the display device in response to hold down of an operation button of the remote controller. Based on the remote control code transmitted by the remote controller, the display device connects a video device corresponding to the remote controller which transmitted the remote control code among the plural video devices, to a display unit, and the input switching for the display device is done.
Japanese patent laid-open publication No. JP-2004-208290-A.
Non-Patent Document 1: High-Definition Multimedia Interface Specification, Version 1.3a, HDMI Licensing, LLC, California in U.S.A, Nov. 10, 2006.